I watched a fire skink for my friend when he went to florida for a month and I can say compared to my other larger reptiles he was easier to care for...mine are easy to care for now because I’m use to it lol.

To keep a tank warm get a night time bulb..I use the red one.
To keep humidity up limit ventilation. Cover 1/3 of the lid with plexiglass(tanks suck at holding humidity) or put the water bowl on the warm side
Youcan give tap water or bottled. You can use water conditoners for reptiles water if you feel its unsafe
With their little sizes its not expensive to care for. Just replace the uvb bulb every 6 months,buy variety of insects and breed them so you don’t have to keep spending money and replace the substrate as it says.

Plexiglass vary depending on store locations. The bulbs shouldn’t get in the way, when the bulbs are on the tank measure the room you have left for the glass. You’ll need a digital humidity gauge...the digital ones are more accurate then the stick ons. I have the cages misted whenever the humidity drops also certain substrate like cypress mulch holds moisture good and aids in humidity.